Coloe-foeming compounds having



Y certain couplerscompounds having the following I Patented MaylS, 1945i UNITED STATES} PATENT 1 OFF C ERED F. Salminen, Paul W.

was Vittm'n, and Arnold Weissberger, Rochester, N. Y, assignorl Eastman Kodak CompanLRochester, N. Y., a corporationof New Jersey No Drawing.

Application January 12, 1943, Serial No. 472,166 1 1o Clahns. (01. 95 -88) invention relates to photographic colorforming compounds and particularly to colorforming compounds having six -membered rings.

The use of color-forming compounds which react with the development product of primary aromatic amino developing agent to form colored images on photographic development is 'well known and has been the subject or numerous prior patents. The dyes formed in this way are insoluble in water and in the ordinary photographic developing and fixing baths, although the silver images formed simultaneously with them during the photographic development'may be removed from the photographic layer tolleave pure dye images in the layer. The coupler compounds-employed in'this way may be added to the developing solution or in certain cases may be incorporated inthe photographic layer prior to exposure. incorporated in the developer solution, it is desired that they be sufll'ciently soluble in the developer-'solution so that amounts may be used which produce 'suiliciently high dye densities in the resulting photographic image. In many cases, the coupler compounds are not suflciently soluble in the developer and steps must be taken to increase their solubility,- for example, by the introduction of a sulfonic group.

It is an object of the present invention to provide novel photographic coupler compounds having desirable color-forming properties. A further object is to provide coupler compounds which produce dyes of desirable light transmission characteristics for purposes of color photos raphy. A still further object is to provide coupler compounds possessing suiflciently high activity toward theoxidized coupling developer that dyes oi usable dye density may be produced.

These objects are accomplished by. theuse oi.

structural formulas: v,

/ CHa 'l'he iollowing enamples illustrate the com-- When the coupler compounds are substituted amino pounds which we have found suitable for use ac-- cording to our invention:

1 NH-cart N-pbenylimide oi b-utsoonic acid Ber. 19, 2700) a) Nn-co-cm b-aeotylegiino-o-mcthyl :lutaconic t y 1!. Chem. 85, 1750 CH -C Y Py (:automeric iorm oi mummy-2, e-diketo-l-imino piparidino '(J. c. s. (1004) 86., 11

(5) in E 0mm 7 It will be noted that certain 01 the compounds which we have found suitable as coupler compounds having six-membered rings, are amino Compounds 1, 2-and 3' are glutaconic We have glutaconic imides.

found that not an or the six membered m com-- pounds havin: a structure similar to glutaconic acid are suitable for use as color couplers. For

example, the N-phenylimide of fi-phenyl glutaconic acid and the N-phenyl imide of B-methyl glutaconic acid (Ann. 370, '78 and 71) couple very poorly and form photographic images which are not satisfactory in practice.

All of the compounds which we have found suitable for use as couplers have a methylene group betweentwo carbon atoms, one of which is a carbonyl carbon atom, The methylene group is believed to be active in the color-forming reaction to couple with the developer oxidized with the development of the silver halide.

The following example illustrates a developing solution containing one of the coupler compounds used according to our invention:

p-Aminodimethylanilinesulfate grams 2.5 Sodium sulphite anhydrous do 2 Sodium carbonate anhydrous do 20 Potassium bromide do 1 Water to liter 1 N-phenylimide of ,B-phenylamino-glutaconic acid u grams 2 Sodium hydroxide, 10% solution cc 10 For use. B is added to A.

In the foregoing example, We have described adding the coupler compound to the developing solution itself. Although it will essentially be employed in this way, the coupler compound may also be incorporated in the photographic layer prior to exposure and the colored image formed by development of the layer in theprimary aromatic amino developing solution A indicated above. Special dispersing agents may be used for incorporating the coupler compound in the emulsion and in certain cases the coupler may be absorbed or adsorbed to the sensitive salt or may be combined with the sensitive salt as a chemical combination. In the case of multi-layer film, in which color forming compounds may be incorporated in one or more of the layers, it may be necessary to take special precautions to prevent wandering of the coupler compound from the sensitive layer in which it is incorporated. For example, the compounds may be incorporated in an emulsion layer in the manner described in Mannes and Godowsky U. S. Patents 2,304,939 and 2,304,940, granted December 15, 1942.

The specific coupler compounds illustrated aboveproduce various colors upon coupling with the oxidation product of a primary aromatic amino developing agent.- The colors produced are as follows:

Compound 1purp1e to blue. Compound 2--blue .to cyan. Compound 3-blue to cyan. Compound 4blue to cyan. Compound 5-blue to cyan.

The aromatic amino developing agents used with the coupler compounds of our invention include the mono, di and triaminoaryl compounds and their derivatives formed by substitution in the amino group as well as in the ring, such as alkylphenylenediamines and alkyltoluylenediamines.

These compounds are usually used in the salt enediamine hydrochloride and dimethyl=p-phen=- ylenediaminesulphate. The p-aminophenols and their substitution products may also be used where the amino group is unsubstituted. Ail of these compounds have an unsubstituted amino group which enables the oxidation products of the developer to couple with the color-forming compounds to form a dye image.

Our development process may be employed for the production of colored photographic images in layers of gelatin or other carrier, such as collodion, organic esters of cellulose, or synthetic resins. The carrier may be supported by a transparent medium such as glass, a cellulose ester or a non-transparent reflecting medium such as paper or an opaque cellulose ester. The emulsion may be coated as a single layer on the support or as superposed layers on one or both sides of the support. The superposed layers may be differentially sensitized and the dyes formed therein by coupling may be bleached by an oxidizing agent such as chromic acid to colorless soluble compounds. The destruction of the dye in this way does not destroy the silver image and a silver image may be developed, bleached and developed to color a number of times, thus permitting the formation of natural color images in superposed layers as described, for example, in Mannes and Godowslry U. S. Patent No. 2,113,329.

The examplesand compounds set forth in the present specification are illustrative only and it .is to be understood that our invention is to be taken as limited only by the scope of the appended claims.

We claim:

1. A colon-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound having the following formula:

where A is selected from the group consisting of hydrogen and phenyl radicals, B is selected from the group consisting of hydrogen, phenyl and mm radicals, R is selected from the group consisting of hydrogen and alkyl and R is hydrogen.

2. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound comprising a ,B-amino glutaconic imide.

3. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound comprising a sacetyl amino glutaconic imide.

4. A color-forming photographic developer comprising a primaryaromatic amino developing agent and a coupler compound comprising iacetylamino glutaconic imide.

5. A color-forming photographic developer comprising a primary aromatic amino developing agent and a coupler compound comprising glutazine.

6. The method of producing acolored photographic image in a gelatino-silver-halide emulsion layer, which comprises exposing the layer and developing. it with a primary aromatic amino developing agent in the presence of a coupler compound having one 0! the following formulas:

developing agent in the compound comprising -a imide.

8. The method of producing a.color photocomprises exposing the layer and developing it with a primary aromatic amino presencev of a couplerp-amino glutaconic' graphic image and developing it with a in a gelatino-silver-halide emulcomprises exposing the layer primary aromatic amino presence. of a coupler 'fi-acetyl amino gluta sion layer, which developing agent in the compound comprising av conicimide.

. 9. The method of producing a color photographic image in a gelatino-silver-halide emulsion layer, which comprises exposing the layer and developing it with a primary aromatic'aminodeveloping agent in the presence of a coupler compound comprising B-acetyl amino glutaconic imide, r

10..The method of producing a color photographic image in a' gelatino-silver-halide emulsion layer, which comprisesexposing the, layer and developing it with a primary aromaticamino developing agent in the presence of a coupler compound comprising glutazine.

' ILMARI F. SALMINEN. PAUL W. VITI'UM. 7

OLD WEISSBERGEB. 

